package cn.tedu;

public class Demo {
    public static void main(String[] args) {
        F f =new F();
    }
}
class F{
    public Animal get(){
        Animal a = new Animal();
        return a;
    }
}
class s extends F{
    public Cat get(){
        Cat c = new Cat();
        return c;
    }
}
class Animal{}
class Cat extends Animal{}